Author(s): Pereira, Gonçalo ; Barbosa, Pedro ; Vicente, Cláudia S.L. ; Faria, Jorge M.S.
Date: 2025
Persistent ID: http://hdl.handle.net/10362/188930
Origin: Repositório Institucional da UNL
Subject(s): nematicide; phytochemicals; plant-parasitic nematodes; Pratylenchus penetrans; risk assessment; sulphides; Agronomy and Crop Science; SDG 3 - Good Health and Well-being; SDG 13 - Climate Action
Funding Information: Partly funded by Funda\u00E7\u00E3o para a Ci\u00EAncia e a Tecnologia (FCT/MCTES) through projects ref. 2022.00359.CEECIND, DOI: 10.54499/2022.00359.CEECIND/CP1737/CT0002 (NemAct, J.M.S.F.); ref. CEECIND/00040/2018, DOI: 10.54499/CEECIND/00040/2018/CP1560/CT0001 (C.V.); PratyOmics ref. PTDC/ASP-PLA/0197/2020 (10.54499/PTDC/ASP-PLA/0197/2020) and structural funding ref. UIDB/00329/2020, DOI: 10.54499/UIDB/00329/2020 (CE3C), ref. LA/P/0121/2020, DOI: 10.54499/LA/P/0121/2020 (CHANGE); ref. UIDB/05183/2020, DOI: 10.54499/UIDP/05183/2020 (MED); and GreenIT (DOIs 10.54499/UIDB/04551/2020 and 10.54499/UIDP/04551/2020). Publisher Copyright: © 2025 by the authors.
Root lesion nematodes (RLNs) are major plant parasites causing significant global yield losses in a wide range of crops. Current management strategies largely depend on synthetic nematicides, which raise environmental and human health concerns due to their broad-spectrum toxicity and persistence in the ecosystem. Volatile allelochemicals offer a promising, environmentally safer alternative due to their biodegradability and lower toxicity to mammals. In this study, we assessed the nematicidal activity of five allelochemical volatiles—dimethyl sulphide (DMS), dimethyl disulphide (DMDS), trans-cinnamaldehyde (TCA), trans-2-decenal (T2D), and trans-2-undecenal (T2U)—against Pratylenchus penetrans, using direct-contact bioassays, in comparison with the conventional nematicide oxamyl. Additionally, we assessed their environmental behaviour and toxicity profiles through in silico modelling. At 1 mg/mL, TCA, T2D, and T2U exhibited strong activity against P. penetrans, outperforming oxamyl by up to 1.6-fold, while DMS and DMDS showed reduced activity. The environmental risk assessment revealed that these compounds have a lower predicted persistence and bioaccumulation compared with oxamyl or fluopyram, a new generation nematicide. Though these findings boost the potential of these compounds as sustainable alternatives for RLN management, field validation and testing with non-target organisms remain necessary for the development of biopesticides. Nevertheless, this study emphasizes the need for an integrated risk-based assessment in the selection of nematicidal agents, warranting efficacy as well as environmental safety.
